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Bacterial cell-to-cell signals of the diffusible signal factor (DSF) family are cis-2-unsaturated fatty acids that differ in their chain length and branching patterns. Signaling involving DSF family members occurs in diverse bacteria to include plant and human pathogens. In the majority of these organisms, the perception of DSF is linked to turnover of the second messenger cyclic di-GMP by one of two “core” pathways. Additional “accessory” signal transduction pathways can also be found, but are not widely conserved. DSF signaling acts to regulate diverse functions to include biofilm formation and architecture, antibiotic resistance, and the production of virulence factors in pathogens. DSF family signals can also participate in interspecies signaling with other bacteria and interkingdom signaling with the yeast Candida albicans. Such interactions may have importance in modifying microbial behavior during polymicrobial infections.  相似文献   
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A class of linear estimators, called Bayes linear estimators, is developed by finding, among all linear estimators, ones which have least average total mean squared error, averaged over parameter points. Ridge, generalized ridge, restricted least squares, subset least squares, least squares, best, and generalized inverse linear estimators are all either Bayes linear estimators or limits of Bayes linear estimators. Results on Bayes linear estimators are extended to affine estimators. “Bootstrapping” procedures, in which the data are recycled in the guise of prior information, are discussed.  相似文献   
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Regulations, such as the Health Insurance Portability and Accountability Act (HIPAA), establish standards to protect patients' medical records from security breaches. Insiders' prosocial misbehaviour within healthcare organisations can cause significant damage to relevant stakeholders. Such behaviour without malicious intention needs to be better understood and carefully managed from the perspective of prosocial behaviour. For this study, a research model was developed that includes the factors influencing student nurses' intention to disclose patient health information. The model was empirically tested with nursing students in South Korea with a scenario-based experiment. We find that both altruistic (impact on others) and egoistic (impact on the self) motivations are significantly important in raising situational empathy. On the other hand, an egoistic motivation (impact on the self) significantly affects people's perception of their responsibility, which mediates the relationship between situational empathy and prosocial intention to disclose. The implications of our findings are discussed.  相似文献   
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Effects of surface pasteurization on inactivation of Listeria innocua were investigated. Surface temperature, monitored during post-packaging pasteurization, was used to predict the lethality of L. monocytogenes. Temperatures reached 70°C for lean and fat sausages within 9 min of treatment. An inoculation study validated the efficacy of post-processing and the thermal lethality of L. monocytogenes. Pre-cooked sausage and ham, inoculated with approximately 107 CFU/cm2 of L. innocua, were heated to a surface temperature of 70°C. Numbers of L. innocua were reduced by 7 log on surface-inoculated sausage. Guidelines for safe, ready-to-eat meat products are provided for small scale meat processors.  相似文献   
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With the growth in project management as a form of work organisation in many sectors of the economy has come the significant rise in the number of project managers and project team members. This change in work organisation brings issues in forging career paths and determining career support in work situations that are often dynamic, short lived and intense. In the relatively small but substantially robust Australian economy, a unique labour market and the tyranny of distance bring their own difficulties. Innovative and collaborative project structures and increasing prevalence of contract work provide both challenges and opportunities for new career pathways in many industries. A growing percentage of Australia's workforce is employed in project-based or project-oriented organisations, leading to the claim that Australia is a project-based economy. This provided a context for our research into the career paths and the issues of career management for project managers working in a project based economy. Using in-depth interviews with project managers from three industry areas we found generational and gender differences in experiences of work, workplace support and mentoring for career development. For a continued strong performance in this economy, organisations that employ project personnel will need to consider how they will ensure the supply of high quality project professionals into the future.  相似文献   
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